a(n) = (2/3) * Sum_{k>=0} (2*k + 1)^n / 3^k.
A337026
a(n) = (2/3) * Sum_{k>=0} (2*k + 1)^n / 3^k.
Terms
- a(0) =1a(1) =2a(2) =7a(3) =38a(4) =277a(5) =2522a(6) =27547a(7) =351038a(8) =5112457a(9) =83764082a(10) =1524907087a(11) =30536665238a(12) =667096092637
External references
- oeis: A337026